In the manufacture of motors, in particular motors for high current applications, such as starter motors, a stack of armature laminations are pressed onto an armature shaft to define a laminated armature having a plurality of radial slots. Windings are placed in the slots, a commutator assembly is pressed onto the armature shaft, the commutator ends are positioned appropriately for a lap or wave winding, a layer of insulation in the form of a truncated hollow cone is placed between layers of conductive winding ends, and the ends are fastened to commutator segments. The commutator segments are typically provided with risers, in the form of two upstanding portions defining a slot for receiving the winding ends. The risers also act to retain the insulating layer in position while the winding ends are being connected to the commutator segments at the slotted risers. After this step, the commutators are machined to provide a commutation surface, and to trim the ends of the windings protruding from the slotted risers. It is believed that such motors have also been produced with an unmachined riserless commutator with an insulating layer between layers of winding. This would be a complicated manufacturing procedure due to the lack of risers to retain and position the insulating member, and would have a high reject rate in welding or brazing winding ends to the commutator using resistive heating, due to poor contact with the unmachined commutator. The commutator would then be machined to provide a commutation surface and to trim the ends of the winding ends connected to the commutator.
The instant invention provides a solution to these and other problems and difficulties of known manufacturing techniques.